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1.
Cibenzoline, a new class I antiarrhythmic drug, was compared with quinidine in an open crossover study of 20 patients with frequent (greater than 30/hr) premature ventricular depolarizations (PVDs). Eight patients treated with cibenzoline experienced more than 75% reduction in PVD frequency. Cibenzoline completely suppressed ventricular couplets in eight of 17 patients and inhibited ventricular tachycardia (VT) in four of 13 patients. Only four patients (20%) responded to quinidine with a similar reduction in PVDs. Quinidine completely suppressed ventricular couplets in eight of 17 patients and episodes of VT in six of 13 patients. Cibenzoline prolonged PR, QRS, and QTc intervals. Eight patients who had shown more than a 75% reduction of PVDs were treated with cibenzoline for an extended period. At the end of three months, only five of eight patients continued to have 75% or greater reduction of PVDs. At the end of six and 12 months, four of five patients continued to have 75% or greater reduction of PVDs. Cibenzoline was similarly effective in suppressing complex arrhythmias. Thus, cibenzoline was only slightly superior to quinidine in suppressing ventricular arrhythmias. With long-term use of cibenzoline, significant PVD suppression was noted at the end of three months but not afterward.  相似文献   
2.
This paper is part of a systematic literature review and presents methodological issues within studies, investigating therapeutic applications of music in cancer patients. This review focuses on published international research from the USA, Canada, Australia and European countries using four electronic databases: PSYCHINFO, WEB OF SCIENCE, MEDLINE and SCIENCEDIRECT. Thirty-two papers were identified and each paper was coded in terms of sample type, basic research question, research design and methodological details, results and implications for future research. This paper addresses questions related to study design and methodology. It explores and discusses the relative advantages and disadvantages of various approaches.  相似文献   
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There is experimental and epidemiologic evidence that some minerals and trace elements play a role in hypertension. We designed an experiment in which salt and water sources were manipulated to examine the possible impact of this relationship. A strain of rats (Dahl rats) known to become hypertensive with sodium chloride ingestion was used to study the effect of salt source and water source on the induction of hypertension. The group on tap water and table salt had blood pressures (184 mmHg +/- 19) significantly higher than every other group in the experiment. The experimental animals receiving tap water plus table salt had the highest blood pressure levels, although they consumed the lowest quantity of sodium. Analysis of the tap water samples showed "soft water" by analysis of calcium and magnesium concentration. This could adversely affect blood pressure. The relatively high magnesium concentration in sun evaporated sea salt may play a protective role in hypertension induction. The zinc and copper present in tap water may play an exacerbating role.  相似文献   
5.
The DNA sequence of the short (S) genomic component of the equine herpesvirus type 1 (EHV-1)KyA strain has been determined recently in our laboratory. Analysis of a 1353-bp BamHI/PvuII clone mapping at the unique short/terminal inverted repeat (Us/TR) junction revealed 507 bp of Us and 846 bp of TR sequences as well as an open reading frame (ORF) that is contained entirely within the Us. This ORF encodes a potential polypeptide of 219 amino acids that shows significant homology to the US9 proteins of herpes simplex virus type 1 (HSV-1), EHV-4, pseudorabies virus (PRV), and varicella zoster virus (VZV). The US9 polypeptides of the two equine herpesviruses exhibit 50% identity but are twice as large as their counterparts in HSV-1, PRV, and VZV. All five US9 proteins are enriched for serine and threonine residues and share a conserved domain of highly basic residues followed by a region of nonpolar amino acids. DNA sequence and Southern blot hybridization analyses revealed that the Us of EHV-1 KyA differs from the Us of EHV-1 KyD and AB1 in that the ORFs encoding glycoproteins I and E and a unique 10-kDa polypeptide are deleted from the KyA genome. These data demonstrate that the predicted 10-kDa protein unique to EHV-1 is nonessential for replication in vitro and that EHV-1 glycoproteins I and E, like their equivalents in HSV-1 and PRV, are also nonessential. These findings and those reported previously by this laboratory and others reveal that the Us segment of EHV-1 comprises nine ORFs, two of which, US4 and 10-kDa ORF, are unique to EHV-1. The gene order of the Us is US2, protein kinase, gG, US4, gD, gI, gE, 10 kDa, and US9.  相似文献   
6.
Graft-versus-host disease (GVHD) is seen in skin, intestinal mucosa, and liver after autologous stem cell transplantation. We reviewed 681 consecutive patients to estimate the probability of gastrointestinal (GI) GVHD, response to treatment, risk factors for development, and effect on survival. GI GVHD was defined by persistent symptoms, mucosal abnormalities at endoscopy, and histology showing apoptotic crypt cells with or without lymphoid infiltrates. The proportion of patients with GI GVHD was 90/681 (13%). Nausea and vomiting occurred in 90% and diarrhea in 40%. The mean time to developing symptoms was day +15, that to histologically proven diagnosis was day +42, and that to starting prednisone treatment was day +45 after stem cell infusion. Treatment with a short course of prednisone effected durable responses in 79% of patients, and an additional 18% responded to a second course of prednisone. A multivariable logistic regression model demonstrated that the combined factor of a diagnosis of breast cancer or hematologic malignancy and female sex was statistically significantly associated with the probability of GI GVHD (P = .003). Survival in patients with GI GVHD was not statistically different than that in those without GVHD. We conclude that women with breast cancer or hematologic malignancy are more likely to develop GI GVHD after autologous transplantation, and that treatment with prednisone was effective.  相似文献   
7.
Over the past decade, keratorefractive surgery has moved into the mainstream of ophthalmology as improved instrumentation and newer techniques have evolved. These new aspects increase the safety and effectiveness of the various keratorefractive procedures. The introduction of new techniques and knife designs has led to improved results with radial keratotomy. The newly developed arcuate keratome purportedly offers the possibility of improving the predictability of arcuate keratotomy. Keratomileusis and epikeratoplasty have been successful for some difficult refractive states, such as aphakia and high myopia. Intracorneal lenses are showing promise in correcting high refractive errors and may offer an alternative to the more technically challenging lamellar procedures performed for correcting these conditions. Intrastromal ring implants are early in their clinical testing, but may provide an alternative to radial keratotomy for correcting myopia. The predictability, effectiveness, safety, and stability are far from perfect for current procedures, but recent results are encouraging.  相似文献   
8.
To thrive in a capitated managed care environment, health systems must enroll more lives to increase revenue, yet they must also control costs to remain viable. This article is a case study of how a team of junior managers and frontline providers solved this conflict for their government-owned health system. The team used a simple, elegant combination of a basic continuous improvement model and the theory of constraints. Using these tools, the team: Exposed a fundamental assumption that was hampering daily throughput; Shifted resources to key processes, improving overall system performance; Significantly increased primary care access with no increase in cost; and Devised a plan to increase capacity with a resource investment that has a payback period of less than two months. The effort has been so successful that the organization's leadership now requires all managers to attend theory of constraints training and has developed short-term and long-term plans to further exploit the team's gains. Although specific issues will be different in other organizations, the approach used is powerful in its simplicity and is easily replicable.  相似文献   
9.

Introduction

Intrathecal chemoprophylaxis is often administered to patients with diffuse large B-cell lymphoma (DLBCL) to lower the rates of central nervous system (CNS) relapse, although its benefit has not been well-described. Prognostic models, including the CNS-International Prognostic Index (IPI), have been developed to aid in identifying patients at highest risk for CNS relapse.

Patients and Methods

We evaluated 112 patients diagnosed with DLBCL from 2009 to 2016 at Emory Healthcare and classified them as high (n = 44) or low risk (n = 68) for CNS relapse and compared CNS prophylaxis rates and relapse rates between groups. The primary outcome was to compare the CNS relapse rate in high-risk patients who received intrathecal prophylaxis with patients who did not.

Results

Twenty-six patients (14 high-risk and 12 low-risk) received intrathecal prophylaxis. Only 4 of 112 patients experienced a CNS relapse, including 1 in the high-risk group and 3 in the low-risk group. Among 14 high-risk patients who received intrathecal prophylaxis, no patient experienced CNS relapse compared with 1 of 30 high-risk patients without prophylaxis (P = 1.0).

Conclusion

Given the low rates of CNS relapse in this series, it is difficult to discern the impact of current risk stratification combined with intrathecal prophylaxis on outcomes. Our observation that many high-risk patients did not receive prophylaxis, whereas many low-risk patients received prophylaxis emphasizes the need for a standardized approach.  相似文献   
10.
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